Drum lagging material and installation apparatus therefor

ABSTRACT

Disclosed are lagging materials for use on a driven cylindrical pulley or drum for an industrial machine. A lagging material can comprise a seaming element along the cross-machine direction (CD) of each of the opposing ends of the lagging material for forming a seam for seaming opposing ends of a lagging material when brought together. A lagging material can also comprise coatings that increase the Coefficient of Friction of a lagging material when the lagging material is installed onto the drum such that no additional adhesive is required to keep the lagging on the drum circumference when in operation. Also described is an apparatus for installing an on machine seamable lagging including at least two opposed elongate members, such that when the elongate members are drawn together, the lagging material is stretched into a seamable position to be installed on the drum.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to pending U.S. provisional patentapplication No. 61/538,470, filed Sep. 23, 2011 and to pending U.S.provisional patent application No. 61/542,657, filed Oct. 3, 2011, eachentitled “DRUM LAGGING MATERIAL AND INSTALLATION APPARATUS THEREFOR,”and the entirety of each of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

The manufacture of corrugated paper board, or box board, on corrugatormachines is well-known in the art. The manufacture of corrugated paperboard, or box board, on corrugator machines is well-known in the art. Anexemplary description of corrugator machines and their use can be foundin U.S. Pat. No. 6,276,420, the entirety of which incorporated byreference hereby. In the manufacture of corrugated paper board, aso-called core paper is heated by steam, which makes it more pliable,and is then fed into a nip formed between a pair of toothed rollerswhose teeth mesh, thereby corrugating the core paper in a uniform,undulating pattern. Starch paste is subsequently applied to the crestsof the corrugated core paper, which is then mated to a liner paper in aroll nip. There, the corrugated core paper and liner paper are bondedtogether to form a completed sheet, which can then be further processedas desired.

In one machine used for this purpose in the prior art, the nip is formedby one of the toothed or corrugating rolls and a pressure roll. Inanother machine of a more recent design, the nip is extended in therunning direction through the use of a belt instead of a pressure roll.The belt holds the corrugated core paper and liner paper togetheragainst the corrugating roll for a significant portion of itscircumference.

On such machines, corrugator belts pull a continuous sheet of corrugatedboard first through a heating zone, where an adhesive used to bondlayers of the continuous sheet together is dried or cured, and thenthrough a cooling zone. The board is subsequently cut and processed intothe desired shape to be used for making boxes. Frictional forces betweenthe corrugator belt, specifically the face, or board, side thereof, andthe continuous sheet are primarily responsible for pulling the latterthrough the machine. Corrugator belts must travel around cylindricalpulleys or drums in operation. Some of these drums are driven, whichmoves the corrugator belt through the machine as well as the corrugatedboard formed thereon in a continuous manner. A lagging material coversthe drive drum surface in order to, among other things, keep the beltfrom slipping.

Conventional prior art lagging materials are manufactured in endlessform and are typically uncoated or coated on one surface. Also, priorart lagging materials are installed on a drum by adhesive bonding, thatis, using a very strong rubber contact cement like 3M 1300L, whichadheres to the lagging material and to the drum surface. This laggingmaterial is used to provide friction between the belt and driver roll inorder to pull the belt and board through the machine section. There aremany variations of lagging material, for example, woven laggingmaterial, some rubber lagging material, lagging materials havingdifferent shaped surfaces, and so on. None of the prior art laggingstructures have a seam or are on-machine seamable as the gluing processdoes not require it.

Prior art glued lagging materials must be replaced from time to time,either periodically (e.g., annually) or for other reasons. To replaceit, a crew of people has to grind, scrape, and remove all the laggingmaterial and glue off the drum to allow the new glue and lagging to beinstalled. In most cases, this requires several days of work and machinedowntime.

SUMMARY OF THE INVENTION

In one embodiment, a seaming apparatus to install lagging materialdesigned to be on machine seamable comprises at least two opposedelongate members, each elongate member being structured to be placedlongitudinally along the cross-machine direction (CD) of a drum overopposing sides of a seaming area of a lagging material for installationof the lagging material on the drum. A plurality of lagging materialengagement members are attached to each opposed elongate member; and atensioning member is operably engaged with the opposed elongate membersfor drawing the opposed elongate members together in the machinedirection (MD). Each lagging material engagement member is structured toengage a seaming area of the lagging material such that when theelongate members are drawn together, the lagging material is stretchedinto a seamable position to be installed on the drum surface.

In another embodiment, also disclosed is lagging material for use on acylindrical pulley or drum or roll for an industrial machine, thelagging material comprising: a substrate; a seaming area for seamingopposing ends of a lagging material when brought together; and a firstcoating on a drum-contact outer surface of the substrate (i.e., innerwith respect to the drum/drive roll of the machine), wherein the coatingincreases the Coefficient of Friction of the lagging material when thelagging material is installed onto the drum such that no adhesive isrequired to keep the lagging material on the drum. The lagging materialcan further comprise a second coating on the opposite outer surface ofthe substrate. The first or second coating can comprise a coating madefrom a thermoplastic or thermoset material. The coating can be anelastomer and can be selected from the group of a polyurethane, arubber, silicone, and other known elastomeric materials. The coatings oneach side of the lagging may be of made of the same material ordifferent materials.

The lagging substrate can comprise at least one layer selected from thegroup of woven or non-woven fibers and/or yarns or spiral links. Thefibers and/or yarns are selected from the group of: natural fibersand/or yarns and synthetic and/or fibers and/or yarns. The laggingmaterial can also comprise at least two layers. For example, the laggingmaterial can include a woven substrate layer and a fibrous batt materiallayer, the batt material being manufactured and applied by techniquesknown to ordinarily skilled artisans such as carding and needlingrespectively. The lagging material is manufactured such that it isstable in the cross-machine direction (CD). The cross-machine direction(CD) width of a drum of a corrugator machine is typically up to 5 metersor more. The lagging material is also extensible to a degree in themachine direction (MD) along the drum circumference such that it can bestretched sufficiently along the drum surface so as to be seamed on thedrum surface yet also maintain that total length over the service lifeof the lagging material.

The lagging material can comprise a plurality of openings spaced alongthe cross-machine direction (CD) of the seaming area on each of theopposing ends of the lagging material, the openings being configured toreceive the engagement members of an installation apparatus when thelagging material is placed around a drum's outer surface. The laggingmaterial can also comprise each opening being substantially laterallypaired in the machine direction (MD) with an opposing opening on theopposing end of the lagging material. The lagging material can beconfigured to be a lagging for a drum roll in a corrugator machine usedin the manufacture of corrugated packaging board. The uncoated laggingmaterial can be at a weight of from about 6.3 oz/ft2 (1.9 kg/m2) toabout 10.5 oz/ft2 (3.2 kg/m2) and a caliper (thickness) of from about0.162 inches (4.1 mm) to about 0.270 inches (6.9 mm). For example, theuncoated lagging material includes a weight of approximately 7 oz/ft2(2.1 kg/m2) and a caliper (thickness) of approximately 0.180 inches (4.6mm). Where the coated lagging material has only the first coating on thedrum contact side, it can comprise a weight of from about 10.7 oz/ft2(3.3 kg/m2) to about 17.9 oz/ft2 (5.4 kg/m2) and a caliper (thickness)of from about 0.192 inches (4.9 mm) to about 0.320 inches (8.1 mm). Forexample, the coated lagging includes a coated weight of about 11.9oz/ft2 (3.6 kg/m2) and a caliper of about 0.213 inches (5.4 mm). Werethe coated lagging material is coated on both the drum contact and sheetcontact sides, the coated lagging material can comprises a weight offrom about 15.1 oz/ft2 (4.6 kg/m2) to about 25.2 oz/ft2 (7.7 kg/m2) anda caliper (thickness) of from about 0.221 inches (5.6 mm) to about 0.368inches (9.3 mm). For example, the coated lagging can include a coatedweight of about 16.8 oz/ft2 (5.1 kg/m2) and a caliper of about 0.245inches (6.2 mm).

In another embodiment, a method comprises: positioning opposing ends ofa lagging material around a drum's/drive roll's for seaming; attachingan installation device to a plurality of openings on each opposing endof the lagging material, the openings configured to receive engagementmembers of the installation apparatus when the lagging material isplaced around a drum's outer surface; bringing the ends of the laggingmaterial into a seaming position with the installation apparatus; andseaming the lagging material onto the drum. The installation device andthe process of installation of the lagging material on the drumstretches the lagging material onto the drum, and the lagging has asufficient Coefficient of Friction such that no additional adhesive isrequired to keep the lagging in place on the drum during operation ofthe machine.

BRIEF DESCRIPTION OF THE FIGURES

For a more complete understanding of the invention, reference is made tothe following description and accompanying drawings, in which:

FIGS. 1A and 1B are a schematic view of a typical belted section of acorrugator machine.

FIGS. 2A and 2B are a cross sectional views of a lagging material.

FIGS. 3A, 3B and 3C are a respectively a perspective view and a topview, and a side view of and embodiment of the lagging material asinstalled on the drum after stretching and seaming.

FIG. 4A shows a perspective view of an installation apparatus forinstalling a lagging material on a drum.

FIG. 4B is a plan view of a portion of the lagging material installationapparatus.

FIG. 4C is a plan view of lagging material installation apparatus asshown in FIGS. 4A and 4B in conjunction with a lagging material beinginstalled on a drum.

FIG. 4D is a side view of the installation apparatus.

FIG. 5 shows a flow chart for a method of seaming a lagging material ona drum.

It will be noted that the same reference numbers are used to refer tothe same features throughout the Figures.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Initially, although embodiments are disclosed in the context of a drivedrum in a corrugator machine, ordinarily skilled artisans willappreciate that the disclosed embodiments of the lagging material andinstallation device have application to other drive roll covers or otherindustrial machines that include drive drums, such as papermakingmachines and nonwovens manufacturing machinery.

FIGS. 1A and 1B are schematic views of a typical belted section of acorrugator machine. A corrugator machine 50 in FIG. 1A has an uppercorrugator belt 52 and a lower corrugator belt 54 which together supportand pull a corrugated paper product 56 therethrough. After passing overhot plates 62, the upper and lower belts 52, 54 together pull thecorrugated paper product 56 between them, maintaining the speed of theoperation and cooling the paper product 56. Weighted rollers 66 applypressure from within the endless loops formed by belt 52 and belt 54toward one another, so that corrugated paper product 56 may be heldtherebetween firmly as the starch based adhesive (applied upstream fromthe present section) cures. Upon exit from between the upper and lowerbelts 52, 54, the corrugated paper product 56 is cut and/or stacked orfurther processed as required. Drums 25 have lagging material (notshown) installed on their surface.

FIG. 1B shows a doublebacker section in which the upper belt 52 isreplaced with a much shorter corrugator belt 72. In this case, the upperbelt 72 does not pass across the hot plates 62. Instead, the upper belt72 is disposed opposite the lower belt 54 downstream from hot plates 62in what may be referred to as cooling, or pulling, zone 74. In thisvariety of corrugator machine 70, weighted steel shoes push thecorrugated paper product 56 against the hot plates 62. In this case, theupper and lower belts 72, 54 disposed downstream from hot plates 62 pullthe corrugated paper product 56 through the machine 70. As before,weighted rollers 66 apply pressure from within the endless loops formedby belt 72 and belt 54 toward one another, so that corrugated paperproduct 56 is firmly held therebetween as the starch based adhesivecures. Upon exit from between belts 52, 54, the corrugated paper product56 is cut and/or stacked. Drums 25 have lagging material (not shown)installed on their surface.

As will be appreciated, corrugator machines place the belts, and hencethe drive drums 25 and pulleys, under highly stressful and adverseconditions. The belts 52, 54, 74 to operate properly, must move at thespeed of the drum surface as the belt and board move through thesection. This is achieved by applying lagging to the drum surface(s),lagging being a material that wraps around the drum surface and providessufficient friction between the belt's inner surface (nonsheet surface)and the lagging to prevent the belt from slipping.

Conventional prior art lagging is be installed on a drum using a verystrong rubber contact cement like 3M 1300L, which adheres to the laggingand to the drum surface.

Disclosed is a lagging sufficiently elastic in the machine direction(MD) and having other properties, such that it does not requireadhesives such as those above to maintain grip on a drum, and aninstallation apparatus therefor. For example, in one embodiment shown inFIG. 2, disclosed is a double coated lagging material, with a coating onboth the drum surface side (inside) and the belt contact side (outside),such that the inside coating has a Coefficient of Friction to preventthe lagging, once stretched and seamed, from slipping on the drumsurface. As will be understood, although the embodiment shows adouble-sided lagging, as the inside coating has a Coefficient ofFriction to prevent the lagging from the slipping on the drum surface,embodiments also include a lagging material with a coating on only thedrum surface side (inside), and not on the paper belt side.

As will be appreciated, as the belt is wrapping a steel drum, the singleor double-coated lagging prevents the lagging from slipping on the drumand also prevents (or at least minimize) the belt from slipping on thelagging. For example, a coated lagging can have a Coefficient ofFriction of about 7 times greater than that of a conventional lagging,as shown in the Table 1.

TABLE 1 Average of Average of Kstatic Kdynamic Conventional Laggingsteel 0.30 0.26 Coated Lagging steel 1.58 1.41

For such a lagging, it is advantageous to have, among other things, anefficient and effective way to install the lagging on the drum withoutglue adhesive. For example, lagging is replaced on a periodic basis dueto wear or for other reasons. For a conventional prior art laggingmaterial such as that heretofore described, once it is glued to the drumsurface, in order to replace it (e.g. annually) a crew of people have togrind, scrape, and remove all the material off the roll/drum to allowthe new glue and lagging to be installed. In most cases, this requiresseveral days to accomplish while the machine is down and out ofoperation.

In various embodiments the lagging material is configured to be alagging for a corrugator machine drive roll/drum in the manufacture ofcorrugated packaging board. There are many variations of lagging, somewoven, some woven with needled batt, some coated on the belt (or nondrum) surface contact side; however no conventional lagging material hasa cross-machine direction (CD) seam or is made to be on machineseamable. Accordingly, in one embodiment, as shown at FIG. 2, disclosedis a lagging sufficiently elastic in the machine direction and havingother properties such that it does not require strong adhesives or glueto remain on the surface of the drum 25 during operation. For example,in one embodiment, disclosed is a lagging including a double coated 19,20 substrate 17, 18, with a coating 19, 20 on both sides of the laggingmaterial 10, such that the Coefficient of Friction of the stretchedlagging is sufficient for the lagging to remain in place on the exteriordrum surface during operation of the machine and to prevent thecorrugator belt from slipping on the drive drum while moving through thecorrugator machine. The coatings 19, 20 can include thermoset orthermoplastic material. The coating on the outer surface 19 can be thesame as that of the drum-contact surface 20, or can be different (i.e.,a functional coating chosen for desired qualities for the inner/outersurfaces). Coatings 19, 20 can include elastomeric coatings selectedfrom a polyurethane, a rubber, silicone, and other known materials (orcombinations thereof).

In another embodiment, shown at FIG. 2A, a lagging includes a laggingmaterial 10 including a substrate 18 with a single coating 20 on onlythe drum surface side (inside). As will be understood, FIGS. 2A and 2Bare exemplary embodiments of a double coated lagging material and singlecoated lagging material respectively, and the number of substratelayers, materials can vary in other embodiments.

Accordingly, specifications for a lagging material can be configured foruse on industrial machines as described herein. Exemplary weights andcaliper ranges for embodiments of the lagging including (1) an uncoatedsubstrate, (2) a single coated lagging coated only on the drum contactside, or (3) double coated on the drum contact side and sheet contactside are given in Table 2 as follows.

TABLE 2 Low High Low High Nominal Range Range Nominal Range Range Weight(−10%) (+50%) Weight (−10%) (+50%) oz/ft2 oz/ft2 oz/ft2 kg/m2 kg/m2kg/m2 Substrate 7.0 6.3 10.5 2.1 1.9 3.2 Single 11.9 10.7 17.9 3.6 3.35.4 Coated Double 16.8 15.1 25.2 5.1 4.6 7.7 Coated Low High Low HighNominal Range Range Nominal Range Range Caliper (−10%) (+50%) Caliper(−10%) (+50%) inches inches inches mm mm mm Substrate 0.180 0.162 0.2704.6 4.1 6.9 Single 0.213 0.192 0.320 5.4 4.9 8.1 Coated Double 0.2450.221 0.368 6.2 5.6 9.3 Coated

As will be appreciated, the higher end of the range is elevated as theremay be some machines that may need a thicker belt on one of the driverolls so that the effective diameter (e.g., diameter of the rolltogether with thicknesses of the lagging and the corrugator belt) of thetwo drive rolls are the same and they pull the corrugator board at thesame speed.

In one exemplary embodiment, a lagging material 10 of FIG. 2 can be awoven substrate with needled batt fiber 17, 18 formed from 100% percentsynthetic fibers and yarns. As configured for a corrugator machine,specifications of a lagging can be, for example, the uncoated laggingmaterial can be at a weight of about 7 oz/ft2 (2.1 kg/m2) and athickness of about 0.180 inches (4.6 mm), the single coated lagging canweigh about 11.7 oz/ft2 (3.6 kg/m2) and the thickness is about 0.213inches (5.4 mm), and the double coated lagging can weigh about 16.8oz/ft2 (5.1 kg/m2) and the thickness is about 0.245 inches (6.2 mm).

A seamable lagging material can be configured to be installed for use ona cylindrical pulley or drum for an industrial machine. In anotherembodiment, as shown in FIGS. 3A, 3B, and 3C, the lagging material 10 ismade seamable for easy installation and removal from a drum 25. FIGS.3A, 3B and 3C are a respectively a perspective view, a top view and aside view of the lagging material 10 as installed on a drum 25. Thelagging material comprises a seaming area 13 for seaming opposing ends11, 12 of a lagging material 10 when brought together. In FIGS. 3A and3B, The seam area 13 is shown as a clipper hook seam 16, however as willbe appreciated, the seam 16 can include seaming methods or elementsknown in the art of industrial fabrics, such as clipper hook seams,spiral-links, and pin-seams wherein the yarns of the substrate actuallyform seaming loops themselves, or any other seaming method such that theseaming elements for each edge of the lagging can be interdigitated,forming a tunnel in which a pin or pintle 17 can be inserted therein. Sotoo are other non-pintle or pin methods of seaming as known to those ofordinary skill in the art within the scope of disclosed embodiments, asfor example, sewn or seamed webbing where seaming tabs affixed at theends 11, 12 of the lagging material are joined with glue or studs in thethrough direction to seam the fabric. As shown, the ends 11, 12 of thelagging material are connected to the seam 16, and the ends 11, 12 ofthe seam 16 have been connected with a pin.

FIGS. 4A and 4C are respectively a perspective view and plan view of aninstallation device 1 for installing a seamable lagging material 10 ontoa drum surface. The apparatus comprises two opposed elongate members 2,3 each elongate member 2, 3 being structured to be placed longitudinallyalong the cross-machine direction (CD) of a drum 25 over opposing sidesof a seaming area 13 for a seam 16 of a lagging material 10 forinstallation of the lagging material 10 on the drum 25. The elongatemembers 2, 3 can be substantially the same width as the cross-machinedirection (CD) width of the lagging material 10 itself. For example, fora lagging installed on a drum/pulley of a corrugator machine, theelongate member can be about 24 inches (610 mm), which is thecross-machine direction (CD) size/dimension for such a lagging. As willbe understood, corrugator machines can have drums of cross-machinedirection (CD) widths of 5 meters (approximately 200 inches) or more.Thus the lagging material 10 as just described could be applied incircumferential strips, and thus installed on the drum 25 in sectionsuntil the full surface is covered. However, the installation tool can beconfigured to the desired cross-machine direction (CD) width for anylagging size 10, including up to a cross-machine direction (CD) widthwhere a “full size” lagging 10 can be installed in one piece on a drum25.

In one embodiment the each elongate member comprises a base portion 2 a,3 a and an upright portion 2 b, 3 b, such as an angle iron as is shown.For example, each elongate member is aligned in the cross-machinedirection (CD) and placed over each end 11, 12 of a flat (non-continuousand unseamed) lagging 10 that is wrapped around a drum 25 forinstallation thereon. The base of the angle iron is placed along thecross-machine direction (CD) on the drum over one joining end 11 of thelagging 10, and the upright portion 2 b, 3 b of the angle iron standssubstantially perpendicular to the drum. Each elongate member 2 isconfigured to be substantially laterally paired in the machine direction(MD) with an opposing elongate member 3 around the seam area 13 wheninstalling the lagging material 10 on the drum 25. As will beunderstood, while the elongate member is shown as an angle iron, otherembodiments are contemplated. For example, instead of an angle iron, arod or planar element could be structured to act as an installationapparatus.

A plurality of lagging material engagement members 4, 5 can be attachedto each opposed elongate member 2, 3. For example, a plurality of hookelements 4 a, 4 b, 4 c, 5 a, 5 b, 5 c are attached to each respectiveelongate member 2, 3. As shown in FIG. 4A, three lagging materialengagement elements 4 a, 4 b, 4 c, and 5 a, 5 b, 5 c attached to eachopposed elongate member 2, 3. As shown in FIG. 4A, the hooks areattached to the bottom upper surface of the base 2 a, 3 a of theelongate member 2, 3 as the plurality of hook elements 4 a, 4 b, 4 c 5a, 5 b, 5 c are each attached to the angle iron 2,3.

FIG. 4B is a plan view showing the elongate member 2 further comprisingan angle iron; and the plurality of hook elements 4 a, 4 b, 4 c are eachattached to the angle iron 2. For example, in the embodiment three 6inch by ⅛ inch (152 mm by 3.12 mm) hooks 4 a, 4 b, 4 c are welded to thebottom of the angle iron 2, which gives sufficient strength to withstandthe tensile strain on the apparatus 1 when installing the laggingmaterial 10 onto the drum, as described herein.

As will be understood, other embodiments of engagement devices 4, 5 canbe employed, such as clasps. Also, any number of techniques may be usedto attach engagement devices 4, 5 such as welding, screwing, or hookingto an elongated member 2, 3.

As shown in FIGS. 4A-4D, the lagging material engagement members 4, 5are spaced at substantially regular intervals along the cross-machinedirection (CD) of each of the elongate members 2, 3. The substantiallyregular intervals as described herein account for differentials in theintervals for various embodiments. For example, as shown in FIG. 4B, themiddle engagement member 4 b can be somewhat off-center by a measurementsufficient to allow a tensioning member 8 to be operatively included inthe installation apparatus. For example, for an elongate member 2 thatis 24 inches (610 mm) in cross-machine direction (CD), the space betweenengagement member 4 a and engagement member 4 b can be from about 9 toabout 11 inches (from about 228 mm to about 279 mm), and the spacebetween engagement member 4 b and engagement member 4 c can be fromabout 15 to about 13 inches (from about 381 mm to about 330 mm). In anembodiment where each elongate member 2, 3 is similarly made, thisallows for an offset 28 of from about 1 to about 3 inches (25 to about76 mm) between engagement members which are paired in the machinedirection (MD) as described below and shown clearly in FIG. 4C.

Each lagging material engagement member 4, 5 is positioned to engage theseaming area 13 at corresponding openings 14, 15 on the lagging material10. For example, as shown in FIG. 4A, one elongate member 2 has threehooks 4 a, 4 b, 4 c, each of which are positioned to engage one end 11of the lagging material at corresponding openings 14 a, 14 b, 14 c onthe lagging material 10. The hooks 4 a, 4 b, 4 c spaced at substantiallyregular intervals along the cross-machine direction (CD) of the laggingmaterial 10. The opposing elongate member 3 has three hooks 5 a, 5 b, 5c, each of which are positioned to engage an opposing end 12 of thelagging material at corresponding openings 15 a, 15 b, 15 c on thelagging material 10. The hooks 4 a, 4 b, 4 c and 5 a, 5 b, 5 c arespaced at substantially regular intervals of each elongate member alongthe cross-machine direction (CD). The corresponding openings 14 a, 14 b,14 c and 15 a, 15 b, 15 c are also spaced at substantially regularintervals along the cross-machine direction (CD) of the ends of thelagging material 11, 12. This configuration causes the ends of thelagging material 11, 12 to come together and meet in the seaming area 13when the installation apparatus is employed, as discussed herein.

As shown on FIGS. 4A and 4C, each lagging material engagement member 4a, 4 b, 4 c on one elongate member 2 is substantially laterally pairedin the machine direction (MD) with an opposing lagging materialengagement 5 a, 5 b, 5 c member on the opposing elongate member 3. Asshown, hook 4 a is paired in the machine direction (MD) with hook 5 a,hook 4 b is paired in the machine direction (MD) with hook 5 b, and hook4 c is pared in the machine direction (MD) with 5 c. As explained above,the hooks are positioned to engage corresponding openings 14 a, 14 b, 14c and 15 a, 15 b, 15 c in the lagging material, and as such, eachopening 14, 15 is substantially laterally paired in the machinedirection (MD) with an opposing opening 14 a, 14 b, 14 c member on thelagging material 10 when the lagging material is wrapped around a drum25 for installation thereon. As shown, opening 14 a is paired in themachine direction (MD) with hook 15 a, opening 14 b is paired in themachine direction (MD) with hook 15 b, and opening 14 c is paired in themachine direction (MD) with 15 c. Again, as shown in FIG. 4C, a pairingin the machine direction (MD) allows for some differential, as forexample between engagement members 4 b and 5 b, which have an offset 28in the cross machine direction (CD) to allow for a tensioning member 8to be operably engaged with the elongate members.

The apparatus comprises a tensioning member 8 operably engaged with theopposed elongate members 2, 3 for drawing the opposed elongate members2, 3 and consequently the lagging ends together in the machine direction(MD). In one embodiment, the apparatus comprises a plurality oftensioning members 8 a, 8 b, 8 c, but as is apparent, the apparatus canbe configured to have any number of tensioning members 8 n. As shown inFIGS. 4A and 4C, the tensioning device 8 can be an all-screw or threadedbolt. FIG. 4D shows a side view of the one elongate member 2.

In another embodiment, tensioning member 8 can be acome-along winch (notshown). The come-along can operably engaged with the opposed elongatemembers 2, 3 for drawing the opposed elongate members 2, 3 andconsequently the lagging ends together in the machine direction (MD).

As shown, the elongate member 2 is a one quarter inch (6.4 mm) angleiron, the side view showing the upright portion 2 b of the angle iron.Holes 6 a, 6 b, and 6 c are drilled into the angle iron at substantiallyregular intervals. As will be noted, the measurement from hole 6 a toholes 6 b and from hole 6 b to hole 6 c are about the same, and hole 6 bis in the center of the upright portion 2 b.

When opposing elongate members 2, 3 are in an installationconfiguration, as shown in FIGS. 4A and 4C, the inner faces of theupright portions 2 b, 3 b face one another, while the base portions 3 a,3 b laterally extend away from one another. The tensioning members 8 a,8 b, 8 c extend transversely through the holes 6 a, 6 b, and 6 c andcorresponding holes 7 a, 7 b, 7 c on the opposing elongate members 2, 3.As shown in the FIGS. 4A and 4C, the tensioning member 8 is a screw witha bolt end against one outside surface of one upright portion 2 b of theelongate member 2 and a nut 9 on the outside surface of the uprightportion 3 b of the opposing elongate member 2. As shown in FIG. 4C,middle holes 6 b, 7 b in the upright portions 2 b, 3 b of the elongatemembers 2, 3 allow the tensioning member 8 to transversely thread theholes 6 b, 7 b at approximately the center of the installation apparatus1. As explained above, the engagement members 4 b, 5 b are attached tothe elongated members 2, 3 such that they are offset 28 so as to allowthe middle tensioning member 8 to extend transversely between engagementmembers 4 b, 5 b between the offset 28. The tensioning members 8 a, 8 b,8 c are positioned proximate to the respective machine direction (MD)paired lagging material engagement members 4 a,5 a; 4 b,5 b; and 4 c,5c. This causes the tensioning member to place a direct pulling force onthe respective machine direction (MD) paired engagement members 4 a,5 a,4 b,5 b, and 4 c,5 c when the tensioning device is operated to draw theelongated members 2,3 together.

In an embodiment where the tensioning member 8 is a come-along winch(not shown), the come-along can operably engaged with the opposedelongate members 2, 3 for drawing the opposed elongate members 2, 3together in the machine direction (MD) as follows. When opposingelongate members 2, 3 are in an installation configuration, as shown inFIGS. 4A and 4C, the inner faces of the upright portions 2 b, 3 b faceone another, while the base portions 3 a, 3 b laterally extend away fromone another. The tensioning members 8 can be positioned such that a pairof hooks from the winch engages transversely through the holes 6 a and 7a such that the winch can be operated to pull the opposing elongatemembers 2, 3 at that position. The winch can be similarly engaged atholes 6 b and 7 b and again at 6 c and 7 c respectively.

Each lagging material engagement member is structured to engage aseaming area 13 of the lagging material such that when the elongatemembers are drawn together, the lagging material is stretched into aseamable position to be installed on the drum.

Accordingly, a seamable lagging material can be configured to beinstalled for use on a cylindrical pulley or drum for an industrialmachine using an installation apparatus. In another embodiment thelagging material 10 as shown in FIGS. 3A and 3B is configured to beinstalled using embodiments of the installation apparatus 1 as describedin FIGS. 4A-4D. FIGS. 3B and 3C are respectively a perspective view anda top view of the lagging material 10 as installed on the drum 25. Thelagging material comprises a seaming area 13 for seaming opposing ends11, 12 of a lagging material 10 when brought together. In the embodimentshown, the openings are placed on either side of the seam area 13 in thelagging material. The lagging material 10 includes a plurality ofopenings 14, 15 spaced along the cross-machine direction (CD) of theseaming area 13 on each of the opposing ends 11, 12 of the laggingmaterial, the openings configured to receive engagement members 4, 5 ofan installation apparatus 1 when the lagging material 10 is placedaround the drum. As explained above, engagement members 4 a, 4 b, 4 cfrom an installation device 1 are substantially laterally paired in themachine direction (MD) with an opposing lagging material engagement 5 a,5 b, 5 c. The engagement members 4 a, 4 b, 4 c 5 a, 5 b, 5 c, arerespectively positioned to engage corresponding openings 14 a, 14 b, 14c and 15 a, 15 b, 15 c on the lagging material 10. Each opening 14 a, 14b, 14 c on one end is substantially laterally paired in the machinedirection (MD) with an opposing openings 15 a, 15 b, 15 c on the laggingmaterial 10 when the lagging material is wrapped around a drum 25 forinstallation thereon. As can be seen in FIG. 5C, the openings 14 a, 14b, 14 c, 15 a, 15 b, 15 c did not experience rips or tears during theinstallation process with the installation apparatus 1.

A method for installing a lagging material using the device embodimentsdescribed herein is disclosed. Consistent with the embodiments of theinstallation apparatus 1 described in FIGS. 4A-4D, disclosed is a methodcomprising positioning opposing ends 11, 12 of a lagging material 10around a drum 25 into for seaming. As shown in FIG. 5, at block 100 isshown attaching an installation apparatus 1 to a plurality of openings14, 15 on each opposing end 11, 12 of the lagging material, the openings14, 15 being configured to receive engagement members 4, 5 of theinstallation apparatus 1 when the unstretched lagging material 10 isplaced around the drum 25 circumference bringing the ends 11, 12 of thelagging material into a seaming position at the seam area 13 by engagingthe seaming apparatus components to stretch the lagging material in themachine direction (MD) with the installation apparatus 1; and completingthe seam of the lagging material 10 onto the drum 25. The installationof the lagging material 10 on the drum 25 stretches the lagging material10 onto the drum, and the lagging material surface in contact with thedrum surface with a sufficient Coefficient of Friction such that noadhesive is required to keep the lagging from slipping on the drumsurface.

At block 200, the method comprises positioning at least two opposedelongate members 2, 3 longitudinally along the cross-machine direction(CD) of a drum 25 over the opposing sides 11, 12 of a seaming area 13 ofthe lagging material 10 and attaching a plurality of lagging materialengagement members 4, 5 attached to each opposed elongate members 2, 3along the cross-machine direction (CD) to the plurality of openings 14,15, the openings being correspondingly spaced along the cross-machinedirection (CD) of the seaming area 13 on each of the opposing ends 11,12 of the lagging material. At least three of the lagging materialengagement devices correspond to at least three of the spaced openingsat each of the opposing ends 11, 12 of the lagging material 10. Asdescribed above the lagging material engagement members can furthercomprise hook elements, and the method includes engaging each hook at acorresponding opening on the lagging material. The lagging materialengagement members are spaced at substantially regular intervals alongthe cross-machine direction (CD), as described herein.

Consistent with the description of the installation device 1 herein, themethod further comprises engaging each lagging material engagementmember 4 on one elongate member 2 with the openings 14 on one end 11 ofthe lagging material 10, and engaging each lagging material engagementmember 5 on the opposing elongate member 3 with the openings 15laterally positioned in the machine direction (MD) on the opposing end12 of the lagging material 10.

At blocks 300-320, the method comprises bringing the ends 11, 12 of thelagging material together by operating a tensioning member 8 operablyengaged with the opposed elongate members 2, 3 for drawing the opposedelongate members 2, 3 together in the machine direction (MD); whereineach lagging material engagement member 2, 3 is structured to engage aseaming area 13 of the lagging material 10 such that when the elongatemembers 2, 3 are drawn together, the lagging material is stretched intoa seamable position to be installed on the drum. In one embodiment, themethod includes operating a plurality of tensioning members 8 a, 8 b. 8c positioned proximate to each of the engagement members as describedherein. While the apparatus can be configured to have any number oftensioning devices 8 a . . . n, in the embodiment where the tensioningdevice is three threaded bolts or screws, an operator or operatingmechanism could tighten the nuts 9 a, 9 b, 9 c, on each of the screwssuch that the elongate members 2, 3 pull the opposing ends 11, 12 of thelagging material 10 together into a seaming position.

In an embodiment where the tensioning member 8 is a come-along winch(not shown), the come-along winch 8 can be positioned such that a pairof hooks from the winch engages transversely through the holes 6 b and 7b such that the winch can be operated to pull the opposing elongatemembers 2, 3 at that position. For example, as block 300 first engagesthe come-along winch to bring the ends of the lagging material into theseaming position, which may be sufficient to bring the whole seam 16into the seaming position, in which case the method moves directly toseaming at 400. Or, as another alternative, the winch can be similarlyengaged in turns at holes 6 a and 7 a, 6 b and 7 b and again at 6 c and7 c respectively. An operator or operating mechanism could place andoperate the winch at each location 6 a, 7 a; 6 b, 7 b; 6 c,7 c such thatthe elongate members 2, 3 pull the opposing ends 11, 12 of the laggingmaterial 10 together into a seaming position.

At block 400, once all three screws have been tightened or thetensioning member otherwise operated such that the seam 16 is in theseaming position, the lagging material 10 can be seamed on the drum 25as for example, with a pin or pintle.

It will thus be seen that the objects set forth above, among those madeapparent from the preceding description, are efficiently attained and,because certain changes may be made in carrying out the above method andin the construction(s) set forth without departing from the spirit andscope of the invention, it is intended that all matter contained in theabove description and shown in the accompanying drawings shall beinterpreted as illustrative and not in a limiting sense.

What is claimed is:
 1. An apparatus comprising: at least two opposedelongate members, each elongate member being structured to be placedlongitudinally along the cross-machine direction (CD) of a drum or driveroll surface over opposing sides of a seaming area of a lagging materialfor installation of the lagging material on the drum; a plurality oflagging material engagement members attached to each opposed elongatemember; and a tensioning member operably engaged with the opposedelongate members for drawing the opposed elongate members together inthe machine direction; wherein each lagging material engagement memberis structured to engage the lagging material such that when the elongatemembers are drawn together, the lagging material is stretched into aseamable position to be installed on the drum surface.
 2. The apparatusof claim 1, wherein the elongate member comprises: a base portion and anupright portion.
 3. The apparatus of claim 2, wherein the each elongatemember comprises an angle iron.
 4. The apparatus of claim 1, wherein theplurality of lagging material engagement members comprise: a pluralityof hook elements attached to each elongate member.
 5. The apparatus ofclaim 1, wherein the plurality of lagging material engagement membersfurther comprise: at least three lagging material engagement devicesattached to each opposed elongate member.
 6. The apparatus of claim 3,the apparatus further comprising: the elongate member further comprisingan angle iron; and the plurality of hook elements are each attached tothe angle iron.
 7. The apparatus of claim 6, wherein the plurality oflagging material engagement members further comprise: at least threehook elements attached to each angle iron.
 8. The apparatus of claim 7,wherein the apparatus comprises: a plurality of tensioning memberspositioned proximate to each of the hooks.
 9. The apparatus of claim 8,wherein the tensioning member comprises: a screw device.
 10. Theapparatus of claim 1, wherein the tensioning member comprises: aplurality of tensioning members.
 11. The apparatus of claim 10, whereinthe tensioning members are positioned proximate to the lagging materialengagement members.
 12. The apparatus of claim 1, wherein the tensioningmember comprises: a screw device.
 13. The apparatus of claim 1, whereinthe tensioning member comprises: a winch and a come along.
 14. Theapparatus of claim 1, wherein the apparatus comprises: the laggingmaterial engagement members are being spaced at substantially regularintervals along the cross-machine direction (CD).
 15. The apparatus ofclaim 1, wherein each lagging material engagement member is positionedto engage the seaming area at corresponding openings on the laggingmaterial.
 16. The apparatus of claim 15, wherein each lagging materialengagement member comprises a hook positioned to engage the seaming areaat a corresponding opening on the lagging material.
 17. The apparatus ofclaim 16, wherein the hooks are spaced at substantially regularintervals along the cross-machine direction (CD).
 18. The apparatus ofclaim 17, wherein at least one interval between the hooks is spaced at adifferent distance from a second interval between the hooks, thedifferential being configured such that it substantially maintains theregularity of the intervals.
 19. The apparatus of claim 18, wherein thedifferential is configured to create an offset from a tensioning member.20. The apparatus of claim 1, wherein each lagging material engagementmember is substantially laterally paired on one cross machine direction(CD) edge of the lagging material in the machine direction (MD) with anopposing lagging material engagement member on the other cross machinedirection (CD) edge of the lagging material on the opposing elongatemember.
 21. An on-machine seamable lagging material for use on acylindrical pulley or drum for an industrial machine, the laggingmaterial comprising: a substrate; a first coating on a drum-contactinner surface of the lagging; wherein the coating increases theCoefficient of Friction of the lagging material when the laggingmaterial is installed onto the drum such that no additional adhesive isrequired.
 22. The lagging material of claim 21, wherein the coatingcomprises an elastomeric coating made from a thermoplastic or thermosetmaterial.
 23. The lagging material of claim 22, wherein the coatingincludes an elastomer selected from the group of a polyurethane, arubber, silicone, and other known elastomeric materials
 24. The laggingmaterial of claim 21, wherein the lagging material comprises: a seamingarea for seaming opposing ends of the lagging material when broughttogether; and a plurality of openings spaced along the cross-machinedirection (CD) of the seaming area on each of the opposing ends of thelagging material, the openings configured to receive engagement membersof an installation apparatus when the lagging material is placed arounda drum.
 25. The lagging material of claim 24, wherein each opening issubstantially laterally paired in the machine direction (MD) with anopposing opening on the opposing end of the lagging material.
 26. Thelagging material of claim 21, wherein the lagging material is configuredto be a lagging for a drive drum in a corrugator machine for themanufacture of corrugated packaging board.
 27. The lagging material ofclaim 21, wherein the drum contact surface coating increases theCoefficient of Friction of the lagging material when the laggingmaterial is installed onto the drum such that no additional adhesive isrequired.
 28. The lagging material of claim 21, wherein the laggingcomprises: a second coating on the opposite outer surface of thesubstrate.
 29. The lagging material of claim 28, wherein the first andsecond coatings are the same material.
 30. The lagging material of claim28, wherein the first and second coatings are different materials. 31.The lagging material of claim 28, wherein the average static Coefficientof Friction when static is Ks=2.81 and the average dynamic Coefficientof Friction (CoF) is Kd=2.44 for the coated belt and the paper board itis pulling.
 32. The lagging material of claim 21, wherein the averagestatic Coefficient of Friction (CoF) is Ks=1.58 and the average dynamicCoefficient of Friction is about Kd=1.41 for a steel drum.
 33. Thelagging material of claim 21, wherein the lagging material substratecomprises at least one layer selected from the group of woven ornon-woven fibers and/or yarn or spiral links.
 34. The lagging materialof claim 33, wherein the substrate fibers and/or yarns are selected fromthe group of: natural fibers and/or yarns and synthetic fibers and/oryarns.
 35. The lagging material of claim 33, wherein substrate thecomprises: at least two layers.
 36. The substrate of claim 35, whereinthe substrate comprises: a woven substrate layer; and a fiberous battmaterial layer.
 37. The lagging material of claim 21, wherein theuncoated lagging material includes a weight of from about 6.3 oz/ft2(1.9 kg/m2) to about 10.5 oz/ft2 (3.2 kg/m2) and a caliper (thickness)of from about 0.162 inches (4.1 mm) to about 0.270 inches (6.9 mm). 38.The lagging material of claim 37, wherein the uncoated lagging materialincludes a weight of approximately 7 oz/ft2 (2.1 kg/m2) and a caliper(thickness) of approximately 0.180 inches (4.6 mm).
 39. The laggingmaterial of claim 21, wherein the coated lagging material has only thefirst coating on the drum contact side, and comprises a weight of fromabout 10.7 oz/ft2 (3.3 kg/m2) to about 17.9 oz/ft2 (5.4 kg/m2) and acaliper (thickness) of from about 0.192 inches (4.9 mm) to about 0.320inches (8.1 mm).
 40. The lagging material of claim 39 wherein the coatedlagging includes a coated weight of about 11.9 oz/ft2 (3.6 kg/m2) and acaliper of about 0.213 inches (5.4 mm).
 41. The lagging material ofclaim 28, wherein the coated lagging material comprises a weight of fromabout 15.1 oz/ft2 (4.6 kg/m2) to about 25.2 oz/ft2 (7.7 kg/m2) and acaliper (thickness) of from about 0.221 inches (5.6 mm) to about 0.368inches (9.3 mm).
 42. The lagging material of claim 41 wherein the coatedlagging includes a coated weight of about 16.8 oz/ft2 (5.1 kg/m2) and acaliper of about 0.245 inches (6.2 mm).
 43. An on machine seamablelagging material for use on a cylindrical pulley or drum for anindustrial machine, the lagging material comprising: a substrate; acoating on the drum contact inner surface of the substrate; and aseaming element along the cross-machine direction (CD) of each of theopposing ends of the lagging material for forming a seam for seamingopposing ends of a lagging material when brought together.
 44. Thelagging material of claim 43, wherein the lagging material comprises: aplurality of openings spaced along the cross-machine direction (CD) of aseaming area on each of the opposing ends of the lagging material, theopenings configured to receive engagement members of an installationapparatus when the lagging material is placed around a drum/rollcircumference.
 45. The lagging material of claim 44, wherein the laggingmaterial comprises: each opening being substantially laterally paired inthe machine direction (MD) with an opposing opening on the opposing endof the lagging material.
 46. The lagging material of claim 43, whereinthe lagging material is configured to be a lagging for a drive drum in acorrugator machine for the manufacture of corrugated packaging board.47. The lagging material of claim 43, comprising: a first coating on adrum-contact inner surface of the substrate; and wherein the drumcontact surface coating increases the Coefficient of Friction of thelagging material when the lagging material is installed onto the drumsuch that no additional adhesive is required.
 48. The lagging materialof claim 43, wherein the coating comprises an elastomeric coating madefrom a thermoplastic or thermoset material.
 49. The lagging material ofclaim 48, wherein the coating includes an elastomer selected from thegroup of a polyurethane, a rubber, silicone, and other known elastomericmaterials
 50. The lagging material of claim 43 comprising: a secondcoating on the belt contact surface of the substrate.
 51. The laggingmaterial of claim 43, wherein the average static Coefficient of Friction(CoF) is about Ks=1.58 and the average dynamic Coefficient of Frictionis about Kd=1.41 for a steel drum.
 52. The lagging material of claim 50,wherein the first and second coatings are the same material.
 53. Thelagging material of claim 50, wherein the first and second coatings aredifferent materials.
 54. The lagging material of claim 43, wherein thesubstrate comprises at least one layer selected from the group of wovenor non-woven fibers and/or yarns or spiral links.
 55. The laggingmaterial of claim 48, wherein the lagging material substrate comprisesfibers and/or yarns selected from the group of: natural fibers and/oryarns and synthetic fibers and/or yarns.
 56. The lagging material ofclaim 54, wherein the substrate comprises: at least two layers.
 57. Thesubstrate of claim 56, wherein the substrate comprises: a wovensubstrate layer; and at least one fiberous batt material layer.
 58. Thelagging material of claim 43, wherein the uncoated lagging materialincludes a weight of from about 6.3 oz/ft2 (1.9 kg/m2) to about 10.5oz/ft2 (3.2 kg/m2) and a caliper (thickness) of from about 0.162 inches(4.1 mm) to about 0.270 inches (6.9 mm).
 59. The lagging material ofclaim 58, wherein the uncoated lagging material includes a weight ofapproximately 7 oz/ft2 (2.1 kg/m2) and a caliper (thickness) ofapproximately 0.180 inches (4.6 mm).
 60. The lagging material of claim43, wherein the coated lagging material has only the first coating onthe drum contact side, and comprises a weight of from about 10.7 oz/ft2(3.3 kg/m2) to about 17.9 oz/ft2 (5.4 kg/m2) and a caliper (thickness)of from about 0.192 inches (4.9 mm) to about 0.320 inches (8.1 mm). 61.The lagging material of claim 60 wherein the coated lagging includes acoated weight of about 11.9 oz/ft2 (3.6 kg/m2) and a caliper of about0.213 inches (5.4 mm).
 62. The lagging material of claim 50, wherein thecoated lagging material comprises a weight of from about 15.1 oz/ft2(4.6 kg/m2) to about 25.2 oz/ft2 (7.7 kg/m2) and a caliper (thickness)of from about 0.221 inches (5.6 mm) to about 0.368 inches (9.3 mm). 63.The lagging material of claim 62 wherein the coated lagging includes acoated weight of about 16.8 oz/ft2 (5.1 kg/m2) and a caliper of about0.245 inches (6.2 mm).
 64. A method to install an on machine seamablecoated lagging comprising: positioning opposing ends of the coatedlagging material around a drum for seaming, the coated lagging having afirst coating on the drum contact side; attaching an installation deviceto a plurality of openings on each opposing end of the lagging material,the openings configured to receive engagement members of theinstallation apparatus when the lagging material is placed around adrum; bringing the ends of the lagging material into a seaming positionwith the installation apparatus; and seaming the lagging material ontothe drum, whereby the installation of the lagging material on the drumstretches the lagging material onto the drum and the lagging has aCoefficient of Friction such that no additional adhesive is required.65. The method of claim 64, further comprising: positioning at least twoopposed elongate members longitudinally along the cross-machinedirection (CD) of a drum over the opposing sides of a seaming area ofthe lagging material; attaching a plurality of lagging materialengagement members attached to each opposed elongate members along thecross-machine direction (CD) to the plurality of openings, the openingsbeing correspondingly spaced along the cross-machine direction (CD) ofthe seaming area on each of the opposing ends of the lagging material;and bringing the ends of the lagging material together by operating atensioning member operably engaged with the opposed elongate members fordrawing the opposed elongate members together in the machine direction;wherein each lagging material engagement member is structured to engagea seaming area of the lagging material such that when the elongatemembers are drawn together, the lagging material is stretched into aseamable position to be installed on the drum.
 66. The method of claim64, further comprising: attaching at least three of the lagging materialengagement devices to at least three of the correspondingly spacedopenings to each of the opposing ends of the lagging material.
 67. Themethod of claim 66, wherein the lagging material engagement membersfurther comprise hook elements.
 68. The method of claim 64, the methodfurther comprising: operating a plurality of tensioning memberspositioned proximate to the engagement members.
 69. The method of claim64, wherein the lagging material engagement members are spaced atsubstantially regular intervals along the cross-machine direction (CD).70. The method of claim 67 the method further comprising: engaging eachhook at a corresponding opening on the lagging material.
 71. The methodof claim 64, the method further comprising: engaging each laggingmaterial engagement member with the openings on one end of the laggingmaterial, and engaging each lagging material engagement member with theopenings laterally positioned in machine direction (MD) on the opposingend of the lagging material.
 72. The method of claim 64, the methodfurther comprising: positioning the tensioning member between each ofthe engagement members such that the tensioning member can operablyengage the engagement members; engaging the tensioning member with atleast one opening on each engagement member; and operating thetensioning member.
 73. The method of claim 64 wherein the laggingmaterial comprises a second coating on the belt contact side of thelagging, which has a Coefficient of Friction such that there is noslippage between a belt and the drum.
 74. The lagging material of claim28 wherein the lagging material has a Coefficient of Friction such thatthere is no slippage between a belt and the drum.
 75. The laggingmaterial of claim 51 wherein the lagging material has a Coefficient ofFriction such that there is no slippage between a belt and the drum. 76.The lagging material of claim 28, wherein the average static Coefficientof Friction (CoF) is Ks=1.58 and the average dynamic Coefficient ofFriction is about Kd=1.41 for a steel drum.
 77. The lagging material ofclaim 50, wherein the average static Coefficient of Friction (CoF) isabout Ks=1.58 and the average dynamic Coefficient of Friction is aboutKd=1.41 for a steel drum.